MCAT Glycolysis

1st step reaction

Glucose phosphorylated to Glucose 6-Phosphate

1st step enzyme

hexokinase

2nd step reaction

Glucose 6-Phosphate isomerized to Fructose 6-Phosphate

2nd step enzyme

Phosphohexose isomerase

3rd step reaction

Fructose 6-Phosphate phosphorylated to Fructose 1,6-Phosphate

3rd step enzyme

Phosphofructokinase-1

4th step reaction

Fructose 1,6-Phosphate cleaved to Glyceraldehyde 3-Phosphate and Dihydroxyacetone Phosphate

4th step enzyme

aldolase

5th step reaction

Dihydroxyacetone isomerized to Glyceraldehyde 3-Phosphate

5th step enzyme

triose phosphate isomerase

6th step reaction

2 Glyceraldehyde 3-Phosphate reduced to 2 1,3-Bisphosphoglycerate

6th step enzyme

Glyceraldehyde 3-Phosphate dehydrogenase

7th step reaction

2 1,3-Bisphosphoglycerate dephosphorylated to 2 3-Phosphoglycerate

7th step enzyme

Phosphoglycerate Kinase

Which steps invest ATP?

1 and 3

Which steps return ATP?

7 and 10

Which step reduces NAD+ to NADH + H?

6

8th step reaction

2 3-Phosphoglycerate isomerized to 2 2-Phosphoglycerate

8th step enyzme

Phosphoglycerate Mutase

9th step reaction

2-Phosphoglycerate dehydrated to 2 Phosphoenolpyruvate

9th step enzyme

enolase

10th step reaction

2 Phosphoenolpyruvate dephosphorylated to 2 Pyruvate

10th step enzyme

Pyruvate kinase

How many net ATP does Glycolysis produce?

2

How many NADH does Glycolysis produce?

2

Which steps of Glycolysis are irreversible?

1, 3, 7